1. Field of the Invention
The present invention relates in general to a medical instrument for use in laparoscopic surgery. More particularly, the invention relates to a laparoscopic instrument which functions as an irrigator, an aspirator and a blunt dissector.
2. Description of the Prior Art
During a surgical procedure, several layers of tissue must usually be penetrated to reach the operative field. When excising an organ, such as a gallbladder, the tissue surrounding the organ must be penetrated before the organ can be removed. The removal or tearing of such tissue is known as dissection. The tissues being dissected, however, often contain blood vessels, nerves, lymph vessels, and the like, which must not be severed. The technique of blunt dissection is often used to prevent unnecessary damage caused by severing these vessels or nerves.
Blunt dissection, as opposed to sharp dissection, involves the use of a blunt surface to break through the tissue, thereby preventing the damage and bleeding caused by lasers and scapels, the tools of sharp dissection. Hard surgical sponges, generally known as peanuts or Kittner sponges, or a surgeon's fingers are often used as blunt dissectors. A peanut is a tightly wound ball of absorbent material, such as gauze or other woven cotton, which typically is gripped with forceps. The weave of the material acts to abrade the tissue being dissected so that the dissection can be performed by either pulling on the tissue or by forcing the peanut through the tissue.
Laparoscopy, surgery performed through several small incisions made in the body rather than through a single large opening, is quickly becoming the preferred method of performing certain procedures due to the reduced trauma and risk of infection as compared to normal surgical procedures. During a laparoscopic procedure, the operative field is viewed via a laparoscope which is inserted through one opening and the surgery is performed with instruments inserted through the other openings. Since the surgeon's hands remain outside of the patient during laparoscopic procedures, blunt dissectors, besides being used as dissectors, are also used to move organs into view for diagnostic purposes and into their proper anatomical positions following the procedure.
The use of conventional blunt dissectors, such as the peanut, during laparoscopic procedures presents many significant drawbacks. For instance, peanuts, being secured only by forceps, can become loose in the body. Further, the view of the operative field often becomes obstructed by pieces of tissue, blood and other bodily fluids produced during blunt dissection, necessitating the immediate need for both irrigation and aspiration of the operative field. Since it is undesirable to create additional incisions, the dissection must be stopped, the dissector must be removed, and an irrigator and/or aspirator must be inserted to remove the fluid and debris.
Others have attempted to overcome these drawbacks by developing blunt dissectors for use in laparoscopic procedures, but these new devices remain lacking. For example, combined irrigation-suction probes have been designed for performing blunt dissection during laparoscopic procedures, but these new probes have smooth, metal tips which are less effective as blunt dissectors than the textured surface of a peanut.